Titanium base alloys



Patented June 2, 1953 Allegheny Ludlum Steel Corporation, Brackenridge, Pa., a corporation of Pennsylvania No Drawing. Application January 25, 1952, Serial No. 268,333

12 Claims. 1

This invention pertains to new and improved titanium base alloys having ternary or higher metal alloying additions of iron and two or more of the elements chromium, molybdenum and manganese, with oxygen and nitrogen within maximum limits.

Alloys of the type here being considered are suitable for structural purposes and particularly, where impact resistance, tensile strength, good ductility and corrosion resistance are needed, as

in aircraft and somewhat special purpose usages.

It has been an object'of the present invention to provide titanium base alloys for sucha need and particularly, alloys that may be produced with relative ease and economy.

Another object has been to provide improved titanium base alloys having good combinations of tensile, impact and ductility properties.

A further object has been to devise titanium base alloys of a ternary and higher metal alloying content that may be heat treated in a like manner to produce a structure containing a matrix of retained beta phase.

These and other objects will be apparent to those skilled in the art from the following de- In these alloys, the iron-plus alloying-metal content should be less than 10%, but not less than about 5%, with an optimum total .offrom 6 to 9%. That is, from the standpoint. of metal alloying contents herein set forth, ,the above specified ranges apply to the total .iron-plus- .chromium-plus-molybdenum, the total iron-plus- They provide good 30 chromium-plus-manganese, the total iron-plusmolybdenum-plus-manganese, and the total ironplus-chromiumplus -molybdenum-plus-manga nese contents.

The heat treatment of these alloys involves working above and within their alpha-beta phase range of about 1800 to 1000 E, followed by annealing 'in the lower portion of thealpha-beta region from about 900 to 1400 F. to produce a structure of alpha islands in a matrix of retained beta that has good tensile and impact properties. This desirable structure may also be obtained by cooling rapidly from'the upper portion of'or over the alpha beta range, about 1400 to 1800" F., and reheating to a lower portion of this range, about 900 to 1400 F.

To provide and maintain good impact properties, the oxygen and nitrogen gas contents should be kept within the maximums specified. The microstructures of all these alloys are similar.

In making alloying additions to the melts, for best results, ferro -manganese, ferro-chromium, and .ferro-molybdenum are used. By Way of example, the titanium may be supplied in the form of a sponge containing about .10% iron, about .10% oxygen and about 05% nitrogen.

The compositions of these alloys, indicated as A, B,-C and D, are represented by the following Tables 1,11; III and'IV and their properties are illustrated, respectively, by Tables IA, IIA, .lIIA

= and IVA. 1 TABLE I Alloy A General Range 0 0ptimumllange Fe-l. 0-4. 0% Fe-2. 0-3. 5% Crl-. 0-6. 0 Or-Z. 0-5. 0% M0---].. 0-5. 0% M01. 5-4. 5% 0-4). 30% max. 0-0. 20% max. N0. 30% max. N-O. 15% max.

TABLE IA Property data for iron-chromium. molybdenum alloys Heat I 22 5%; Percent Charpy No. Per- Per- Per Per- ,Per- 5, E1 R. A. Impact cent cent cent cent cent (Ft-lb.)

K-482; 2. 0 2. 8 1. 2 0. 1 0. 05 125, 300 15. 5 42. 8 26. 0 K-51L" 2. 1 2. 1 1. 8 0. 1 0. 05 127, 500 13. 0 45. 2 42. O CK-483 2. 2 1. 4 2. 4 0.1 0. 05 140, 300 16. 5 51. 0 13. O K-501--. 2. 9 2. 1 3. 0 0. 1 O. 05 144, 14. 0 43. 4 y 26. 0 K-480.-. 2. 8 2. 8 2. 4 O. 1 O. ()5 16 2, 200 12. 0 24. 0 18. 0 K489--- 2.3 v 2. 2. 4 .0. 2 0. 05 152, 100 15. 0 21. 2 12. 0 K490--- 2. 8 2. 8 2. 4 0. 1 I 0. 15 162, 200 13. 0 30. 8 V 14. 5 K-498... 2. 7 3. 5 1. 8 0. 1 0. 05 153, 300 15. 0 39. 9 v 25. 0 K-502.-- 3. 3 5. 3 1. 5 O. 1 0. 05 155, 000 15. 5 39. 9 r 18. 0 K-481.-. 3. 5 3. 5 3. O I 0. 1 0. 05 155, 300, 14. 0 35. 5 10. 0 'K-487.. 3. 8 1. 4. 5 0. 1 0. 05 162, 800 12. 5 36. 1 22.0

TABLE 11 Alloy B General Range I .Optimum Range Property data for irowohromsum manganese allege forged fmm 1700 F., annealed at 1300" F.

Composition v t Tensile Per- Heat Percent Oharpy No. Per- Per- Per- Per- Per- R. A. Impact cent eentcent cent cent (Ft.lb)

Fe Cr Mn 02 N2 K-534-.- 1.4 2.1 2.5 0.1 0.05 151,000 24.0 35.5 20.5 K-'56.-- 1.7 2.1 4.2 0.1 0.05 4 100,000 3.0 13.3 10.0 K-555 1.3 23 3.4 0.1 0.05 130,000 10.0 19.3 3.0 K-560-.. 1.3 2.3 3.4 0.3 0.05 192,000 5.0 4.2 7.0 K-561 1.3 2.3 3.4 0.1 0.25 131,000 10.0 15.5 7.0 K523-- 2.3 as 4.2 0.1 0.03 r 100,300 11.0 20.1 0.0

TABLE III What I claim is as follows:

Allgy g 1. An improved. titanium base alloy which contains about 1 to 4% iron, upto about 30% maxi- General Range Uptimum Range mum of each of the gases oxygenand nitrogen,

30 and at least two metals within the ranges speci- Fe-1.0-4.0% -15-2102; fied from the group consisting of: chromium Kai-5 about .5;to- 6%, manganese about .5 to 6%, and 00.30%.max.. o-0.20% 1:11am. molybdenum about .5 to 5%; the i-ron-plus-alloy- NH115941111111 ing metal content being less-than 10% but not less than about 5% the: alloy being characterized TABLE IIIA Property data for iroamolgbdemmt-manganese alloys forged from 1100 It, annealed at 1.300 F.

Clomgosition; V

Tensile ,Permatch Heat 1 Percent Char No. Per- Pen. Per- -Pe:- ;Ben ILA. Imps? cent cent cent cent 'cent (Ft-lb) 1E0 1010-1101 02 N2 K-509- 1.7 I.8' 0.1 0.00; 140,500 21.0 37.3 20.0- K-550..- 2.0 1.3 4.2 0.1 0-0.3. 132,000 10.0 19.0 10.0, K-543 2.2 2.4 I 3.4 0.1 0. 03'- 173, 500- 10.0 25.5 10.0 K-l 2.2 2.4 3.4 0.3 0.05 153,000 12.0- 11.0 7.0 K-552 2.2 2.4 3.4 0.1 0.25 133,000 0.0 13.3 5.5 K-549.-- 2.5 3.0 2.5 I 0.1 0.05 102,000 13.0 30.1 1015.

TABLE IV 0 by its good ductility and impact strength with Alloy D relatively high tensile strength.

2. improved titanium base alloy as defined. GeneraLRange Optimum Range in claim I as heat treated by Working above and I within its alpha-beta; phase range of about 1800" e.l.0'4.0%. ge-ream'. to=1000- R, followed by annealing ina lower porfijg tion. of its alpha-beta region; of. about 900 to %111 g 5-0. &% lgngbHi-fiit 11400 and. wherein. its structure has alpha. Z j 3 g; islands in a. matrizr of retained beta.

, 3. An zmproved t1tamum base alloy as defined TABLE'TVK Property data for irawchromium-molybdenwm-mangzmese alloys forged from 1700" .F., amwolert at 1800" F.

Composition. V th Tensile .Per- 6 Percent Char 5 Heat N0 Per- Per- Per Per Per- -Perg g R.-A. Impa t cent cent cent cent cent .cent (Ft. lb)

Fe-Cr fMo= Mm O2 3N2,

1.2 111 0.10 005 159.000 24.0 49.3 24.0 13.2 1;? 0.30 005" 2 149.000 10.0 5.5 20.0 1 2 117- 0.10 025 1 153.000 15.0 19.0 13.0 1.0 2r 0.10 003 1114;000 -120- 13.3 11.0 1.2 1:1 0.10 0.05 130300 12.0: 32.3 2:4- 1:? 0.10 0.05: 1'32;000 10.0 20.7 0.0 1 3- as 0.10 ;0.05 E 500 3.0-, 21.3 10.0 1.5 2.0 0.10 005* 132.000 14.0 35.5 0.0

in claim 1 as treated by rapidly cooling it from an upper portion to slightly above its alpha-beta phase range of about 1400 to 1800 F., followed by reheating to the lower portion of such range, about 900 to 1400 F., and wherein its structure has alpha islands in a matrix of retained beta.

4. An improved titanium base alloy which contains about 1 to 4% iron, up to about .30% maximum of each of the gases oxygen and nitrogen, at least two metals within the ranges specified from the group consisting of: chromium about .5 to 5%, manganese about .5 to 6%, and molybdenum about .5 to 5%, the iron-plus-alloying metal content being less than 10% but not less than about 5%, and the balance titanium with incidental impurities.

5. An improved titanium base alloy which contains about 1 to 4% iron, up to about 30% maximum of each of the gases oxygen and nitrogen, about 1 to 6% chromium, about 1 to 5% molybdenum, the iron-plus-alloying metal content being less than 10% but not less than about 5%, and the balance titanium with incidental impurities.

6. An improved titanium base alloy which contains about 2 to 3.5% iron, up to about .20% maximum oxygen and about .15.% maximum nitrogen, about 2 to 5% chromium, about 1.5 to 4.5% molybdenum, the iron-plus-alloying metal contact being less than 10% but not less than 5%, and the balance titanium with incidental impurities.

'7. An improved titanium base alloy which contains about 1 to 3% iron, up to about .30%

manganese, the iron-plus-alloying metal content being less than 10% but not less than about 5%, and the balance titanium with incidental impurities.

8. An improved titanium base alloy which contains about 1.5 to 2.5% iron, up to about 20% maximum oxygen and about .15% maximum nitrogen, about 2 to 4% chromium, about 2 to 4.5%

manganese, the iron-plus-alloying metal content being less than 10% but not less than about 5%, and. the balance titanium with incidental impurities.

9. An improved titanium base alloy which contains about 1 to 4% iron, up to about 30% maximum of each of the gases oxygen and nitrogen, about 1 to 5% molybdenum, about 1 to 6% manganese, the iron-plus-alloying metal content being less than 10% but not less than about 5%, and the balance titanium wit-h incidental impurities.

v 10. An improved titanium base alloy which contains about 1.5 to 3% iron, up to about 20 maximum oxygen and about 15% maximum nitrogen, about 1.5 to 4% molybdenum, about 2 to 4.5% manganese, the iron-plus-alloying metal content being less than 10% but not less than about 5%, and the balance titanium with incidental impurities.

11. An improved titanium base alloy which contains about 1 to 4% iron, up to about .30% maximum of each of the gases oxygen and nitrogen, about .5 to 5% chromium, about .5 to 5% molybdenum, about .5 to 6% manganese, the ironplus-alloying metal content being less than 10% but not less than about 5%, and the balance titanium with incidental impurities.

12. An improved titanium base alloy which contains about 1.5 to 3.5% iron, up to about .20% maximum oxygen and about .15% maximum nitrogen, about 1.5 to 3.5% each of chromium and manganese, about 1 to 3% molybdenum, the iron-plus-alloying metal content being less than 10% but not less than about 5%, andthe balance titanium with incidental impurities.

RICHARD K. PITLER.

No references cited. 

4. AN IMPROVED TITANIUM BASE ALLOY WHICH CONTAINS ABOUT 1 TO 4% IORN, UP TO ABOUT .30% MAXIMUM OF EACH OF THE GASES OXYGEN AND NITROGEN, AT LEAST TWO METALS WITHIN THE RANGES SPECIFIED FROM THE GROUP CONSISTING OF: CHROMIMUM ABOUT 5 TO 5%, MANGANESE ABOUT .5 TO 6%, AND MOLYBDENUM ABOUT .5 TO 5%, THE IRON-PLUS-ALLOYING METAL CONTENT LESS THAN 10% BUT NOT LESS THAN ABOUT 5%, AND THE BALANCE TITANIUM WITH INCIDENTAL IMPURITIES. 